xe2x80x9cFlexures Which Reduce Friction In An Actuator For Data Storage Devicexe2x80x9d, Ser. No. 324,580 filed concurrently herewith, is incorporated herein by reference.
This invention relates to a linear actuator for carrying read/write heads into engagement with a recording medium and more particularly, to a linear actuator with a carriage which is movable along a central guide track.
U.S. Pat. No. 4,740,851-Jones, et al and U.S. Pat. No. 4,663,677-Griffith, et al show removable media magnetic disk drives of the type made by the assignee of the present invention. A cartridge having a flexible recording medium is inserted into the disk drive. A motor rotates the disk which is engaged by magnetic read/write heads.
Rotary and linear actuators have been used to carry the magnetic heads into engagement with the disk. Linear actuators have been used for magnetic disk drives, CD players and optical recording drives. These actuators typically use a voice coil motor to move the carriage of the actuator. In the prior art, the main bearings and the coil are placed away from the line of travel of the heads. This frequently causes binding forces and resonance problems.
It is an object of the present invention to provide a lightweight, low mass, actuator which avoids the problems of the prior art.
In accordance with the present invention, a linear actuator has a lightweight carriage which is linearly movable along a central guide track. The carriage has bushings which travel along a cylindrical wire guide. The bushings and coil are spaced symmetrically with respect to the heads so that the center of mass, center of friction, center of force, and center of stiffness are all aligned along the central wire guide. This arrangement minimizes friction and mass and avoids binding forces and resonance problems.
The foregoing and other objects, features and advantages of the invention will be better understood from the following more detailed description and appended claims.